Vanguard is carving out its $900b wealth and advice business into a separate unit to speed investment and meet rising demand. Long a dominant participant in low-cost and index funds, Vanguard has been pushing into personalized advice since 2015 as a way of tapping new revenue sources and staying close to customers. The move comes as traditional asset managers fend off rising competition from fintechs, banks and alternative asset specialists and respond to client demand for help navigating an increasingly complex investment landscape.